کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1346215 | 1500362 | 2011 | 6 صفحه PDF | دانلود رایگان |
A novel, highly efficient method has been developed for the separation of the optical isomers of 1-[2-carboxy-6-(trifluoromethyl)phenyl]-1H-pyrrole-2-carboxylic acid with methyl (R)-2-phenylglycinate. The structural aspects of chiral discrimination have been discussed via comparison of the molecular structures and the packing energies of the diastereoisomeric salts determined by single crystal X-ray diffraction measurements. Reciprocal resolution and a new, highly efficient second order asymmetric transformation of racemic methyl 2-phenylglycinate with the pure enantiomer of the previously resolved atropisomeric carboxylic acid are also reported.
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(Sa)-1-[2-Carboxy-6-(trifluoromethyl)phenyl]-1H-pyrrole-2-carboxylic acidC13H8F3NO4ee 96% (HPLC)[α]D25=-43.1 (c 1.0, EtOH)Source of chirality: resolution with methyl (R)-2-phenyl-glycinateAbsolute configuration: (Sa)
Methyl (R)-2-phenylglycinateC9H11NO2ee 95% (HPLC)[α]D25=-154 (c 1.0, EtOH)Source of chirality: resolution with (S)-1-[2-carboxy-6-(trifluoromethyl)phenyl]-1H-pyrrole-2-carboxylic acidAbsolute configuration: (R)
Journal: Tetrahedron: Asymmetry - Volume 22, Issues 20–22, 30 November 2011, Pages 1879–1884